﻿350 
  H. 
  G. 
  SEELEY 
  ON 
  tfEUSTICOSAURUS 
  PUSILLUS. 
  

  

  36. 
  On 
  Neusticosaurus 
  pusillus 
  (Fraas), 
  an 
  Amphibious 
  Reptile 
  

   having 
  Affinities 
  with 
  the 
  Terrestrial 
  Nothosauria 
  and 
  

   with 
  the 
  Marine 
  Plesiosauria. 
  By 
  H. 
  G. 
  Seeley, 
  Esq., 
  F.R.S., 
  

   F.G.S., 
  &c, 
  Professor 
  of 
  Geography 
  in 
  King's 
  College. 
  (Read 
  

   March 
  22, 
  1882.) 
  

  

  [Plate 
  XIII.] 
  

  

  Mr. 
  Julius 
  Hoser, 
  of 
  Stuttgart, 
  submitted 
  to 
  me 
  in 
  June 
  1881 
  

   two 
  of 
  the 
  most 
  interesting 
  Saurians 
  ever 
  discovered 
  in 
  the 
  Trias. 
  

   They 
  were 
  found 
  in 
  the 
  Lettenkohle, 
  which 
  lies 
  between 
  the 
  Upper 
  

   Muschelkalk 
  and 
  the 
  Keuper, 
  in 
  a 
  quarry 
  at 
  Hohencck, 
  near 
  

   Ludwigsburg, 
  about 
  nine 
  miles 
  north 
  of 
  Stuttgart. 
  These 
  fossils 
  are 
  

   the 
  materials 
  briefly 
  noticed 
  by 
  Dr. 
  Oscar 
  Fraas 
  in 
  the 
  ' 
  Wiirttem- 
  

   bergische 
  Jahresheftc,' 
  1881, 
  and 
  figured 
  as 
  Simosaurus 
  pusillus. 
  

   This 
  animal 
  is 
  probably 
  the 
  smallest 
  representative 
  of 
  the 
  Plesio- 
  

   sauria 
  yet 
  exhumed 
  ; 
  but 
  it 
  has 
  a 
  greater 
  interest 
  in 
  exhibiting 
  in 
  

   the 
  hind 
  limbs 
  all 
  the 
  characteristics 
  of 
  a 
  land 
  animal, 
  while 
  the 
  

   fore 
  limbs 
  have 
  become 
  paddles, 
  in 
  which 
  a 
  more 
  striking 
  approxi- 
  

   mation 
  is 
  made 
  to 
  Plesiosaurus 
  than 
  was 
  previously 
  known 
  in 
  any 
  

   Triassic 
  representative 
  of 
  this 
  order. 
  Yet, 
  in 
  form 
  of 
  vertebra) 
  and 
  

   proportions 
  of 
  the 
  vertebral 
  column, 
  in 
  structure 
  of 
  the 
  pectoral 
  

   and 
  pelvic 
  girdles 
  and 
  conformation 
  of 
  their 
  component 
  bones, 
  the 
  

   Plesiosaurian 
  common 
  plan 
  is 
  so 
  closely 
  adhered 
  to 
  that 
  no 
  doubt 
  can 
  

   attach, 
  to 
  the 
  animal's 
  systematic 
  position. 
  A 
  photograph 
  showing 
  

   the 
  condition 
  of 
  the 
  principal 
  slab 
  when 
  first 
  discovered, 
  which 
  was 
  

   taken 
  as 
  a 
  record, 
  in 
  case 
  of 
  accident 
  during 
  its 
  development 
  from 
  

   the 
  matrix, 
  satisfactorily 
  attests 
  that 
  the 
  bones 
  are 
  in 
  their 
  natural 
  

   positions, 
  and 
  thus 
  enables 
  us 
  to 
  recognize 
  in 
  this 
  animal 
  a 
  terres- 
  

   trial 
  Plesiosaurian 
  in 
  process 
  of 
  undergoing 
  those 
  structural 
  modi- 
  

   fications 
  which 
  would 
  adapt 
  it 
  for 
  aquatic 
  life. 
  

  

  This 
  is 
  the 
  first 
  occurrence 
  of 
  a 
  fairly 
  complete 
  Plesiosaurian 
  

   skeleton 
  in 
  the 
  Trias. 
  None 
  of 
  the 
  remains 
  so 
  admirably 
  illus- 
  

   trated 
  by 
  von 
  Meyer, 
  and 
  referred 
  to 
  Nothosaurus, 
  Pistosaurus, 
  

   Conchiosaurus, 
  and 
  Simosaurus, 
  exhibit 
  the 
  skull 
  in 
  association 
  

   with 
  the 
  vertebral 
  column, 
  or 
  either 
  with 
  the 
  limb-bones. 
  The 
  

   latter, 
  indeed, 
  have 
  only 
  been 
  recovered 
  in 
  isolation 
  from 
  each 
  other 
  ; 
  

   and 
  though 
  the 
  association 
  of 
  bones 
  in 
  certain 
  quarries 
  fully 
  justified 
  

   von 
  Meyer 
  in 
  his 
  cautious 
  reference 
  to 
  NoiJwsaurus 
  of 
  the 
  various 
  

   elements 
  of 
  the 
  skeleton, 
  no 
  restoration 
  has 
  been 
  attempted. 
  Even 
  

   in 
  the 
  admirable 
  analysis 
  of 
  the 
  characters 
  of 
  this 
  genus 
  given 
  by 
  

   Prof. 
  Owen 
  in 
  his 
  ' 
  Palaeontology 
  ' 
  (2nd 
  edit.), 
  the 
  diagram 
  (fig. 
  90, 
  

   p. 
  230) 
  of 
  principal 
  characters 
  represents 
  the 
  fore 
  limb 
  as 
  unknown*. 
  

   In 
  studying 
  this 
  new 
  fossil 
  we 
  need 
  to 
  remember 
  that 
  the 
  genus 
  

   Simosaurus 
  is 
  founded 
  upon 
  the 
  skull, 
  of 
  which 
  both 
  superior 
  and 
  

   inferior 
  aspects 
  are 
  well 
  known 
  f 
  . 
  

  

  * 
  Von 
  Meyer 
  would 
  have 
  regarded 
  the 
  limb 
  represented 
  as 
  a 
  fore 
  limb, 
  

   t 
  Fauna 
  der 
  Vorwelt, 
  Saurier 
  des 
  Muschelkalkes, 
  pis. 
  16-20, 
  

  

  

  